In recent years, an imaging apparatus (hereinafter, sometimes referred to as an optical coherence tomography (OCT) apparatus) that captures a tomographic image (hereinafter, sometimes referred to as an optical coherence tomographic image) of an inspection object using an optical coherence tomography (OCT) utilizing interference by a low-coherence light has been used in the medical field, particularly in the ophthalmic field. Since an OCT apparatus utilizes the properties of light, the OCT apparatus can acquire tomographic images at high resolution on a micrometer base which is an order of wavelength of light.
When a fundus of a subject's eye is measured, for example, an examinee may sometimes move, blink, or make slight movement (involuntary eye movement during visual-fixation) at random during measurement. For this reason, there is an issue that the tomographic image of the subject's eye acquired by the OCT apparatus will be distorted.
In order to acquire a three-dimensional structure of a pupil at a high speed, an OCT which irradiates the pupil (anterior eye portion) with a plurality of measurement light beams is discussed in Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2008-508068. Since an irradiating region per one measurement light beam can be narrowed, the three-dimensional structure can be captured at a high speed.